diff --git a/.travis.yml b/.travis.yml
index 5e63fb7e..efe4e1c1 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -13,8 +13,13 @@ install:
   - pip install -e .[dev]
 
 script:
-  - pytest --cov loguru/
+  - pytest --cov
 
 after_success:
-  - codecov --flags "py${TRAVIS_PYTHON_VERSION//./}"
+  # Report to codecov, with different flags for tests.
+  - coverage xml --include 'loguru/*'
+  - codecov -f coverage.xml --flags loguru "py${TRAVIS_PYTHON_VERSION//./}" --disable search gcov pycov
+  - coverage xml --include 'tests/*'
+  - codecov -f coverage.xml --flags tests "py${TRAVIS_PYTHON_VERSION//./}" --disable search gcov pycov
+
   - cd docs && make html
diff --git a/codecov.yml b/codecov.yml
new file mode 100644
index 00000000..8c4ad746
--- /dev/null
+++ b/codecov.yml
@@ -0,0 +1,10 @@
+coverage:
+  status:
+    project: yes
+    patch: yes
+    changes: yes
+
+comment:
+  layout: "header, diff"
+  behavior: default
+  require_changes: no
diff --git a/tests/exceptions/enqueue_with_others_handlers.py b/tests/exceptions/enqueue_with_others_handlers.py
index d28ac9f0..81db1918 100644
--- a/tests/exceptions/enqueue_with_others_handlers.py
+++ b/tests/exceptions/enqueue_with_others_handlers.py
@@ -4,8 +4,6 @@
 
 def check_tb_sink(message):
     exception = message.record["exception"]
-    if exception is None:
-        return
     assert exception.traceback is not None
 
 
diff --git a/tests/exceptions/nested_wrapping.py b/tests/exceptions/nested_wrapping.py
index f97b7001..3f634474 100644
--- a/tests/exceptions/nested_wrapping.py
+++ b/tests/exceptions/nested_wrapping.py
@@ -24,9 +24,6 @@ def a(x):
 
 
 try:
-    try:
-        f(0)
-    except ZeroDivisionError:
-        logger.exception("")
-except Exception:
+    f(0)
+except ZeroDivisionError:
     logger.exception("")
diff --git a/tests/exceptions/not_enough_arguments.py b/tests/exceptions/not_enough_arguments.py
index 007e39d5..77db4a2b 100644
--- a/tests/exceptions/not_enough_arguments.py
+++ b/tests/exceptions/not_enough_arguments.py
@@ -7,11 +7,11 @@
 
 @logger.catch
 def decorated(x, y, z):
-    pass
+    raise NotImplementedError
 
 
 def not_decorated(x, y, z):
-    pass
+    raise NotImplementedError
 
 
 decorated(1)
diff --git a/tests/exceptions/output/enqueue_with_others_handlers.txt b/tests/exceptions/output/enqueue_with_others_handlers.txt
index 0a9854d1..8d69512f 100644
--- a/tests/exceptions/output/enqueue_with_others_handlers.txt
+++ b/tests/exceptions/output/enqueue_with_others_handlers.txt
@@ -1,7 +1,7 @@
 
 Traceback (most recent call last):
 
-> File "tests/exceptions/enqueue_with_others_handlers.py", line 19, in <module>
+> File "tests/exceptions/enqueue_with_others_handlers.py", line 17, in <module>
     1 / 0
 
 ZeroDivisionError: division by zero
diff --git a/tests/exceptions/output/nested_wrapping.txt b/tests/exceptions/output/nested_wrapping.txt
index 137c0a9d..05decf41 100644
--- a/tests/exceptions/output/nested_wrapping.txt
+++ b/tests/exceptions/output/nested_wrapping.txt
@@ -30,7 +30,7 @@ ZeroDivisionError: division by zero
 
 Traceback (most recent call last):
 
-> File "tests/exceptions/nested_wrapping.py", line 28, in <module>
+> File "tests/exceptions/nested_wrapping.py", line 27, in <module>
     f(0)
     └ <function f at 0xDEADBEEF>
 
diff --git a/tests/exceptions/too_many_arguments.py b/tests/exceptions/too_many_arguments.py
index 93d90828..14689b6b 100644
--- a/tests/exceptions/too_many_arguments.py
+++ b/tests/exceptions/too_many_arguments.py
@@ -7,11 +7,11 @@
 
 @logger.catch
 def decorated():
-    pass
+    raise NotImplementedError
 
 
 def not_decorated():
-    pass
+    raise NotImplementedError
 
 
 decorated(1)
diff --git a/tests/test_add_options.py b/tests/test_add_options.py
index 35051d7c..21e779f8 100644
--- a/tests/test_add_options.py
+++ b/tests/test_add_options.py
@@ -363,7 +363,7 @@ def test_disabled_logger_in_sink(sink_with_logger):
 
 def test_invalid_function_kwargs():
     def function(message, a="Y"):
-        pass
+        raise NotImplementedError
 
     logger.add(function, b="X", catch=False)
     with pytest.raises(TypeError):
@@ -384,7 +384,7 @@ def __init__(self):
             self.out = ""
 
         def write(self, m):
-            pass
+            raise NotImplementedError
 
     writer = Writer()
     logger.add(writer, format="{message}", kw1="1", kw2="2", catch=False)
diff --git a/tests/test_exceptions_formatting.py b/tests/test_exceptions_formatting.py
index 0f19f379..012276a6 100644
--- a/tests/test_exceptions_formatting.py
+++ b/tests/test_exceptions_formatting.py
@@ -21,7 +21,7 @@ def normalize(formatted_exception):
     return formatted_exception
 
 
-def generate(output, outpath):
+def generate(output, outpath):  # pragma: no cover
     """Generate new output file if exception formatting is updated"""
     with open(outpath, "w") as file:
         file.write(output)
diff --git a/tests/test_threading.py b/tests/test_threading.py
index 82f00517..49b5eec0 100644
--- a/tests/test_threading.py
+++ b/tests/test_threading.py
@@ -11,8 +11,7 @@ def __init__(self, sleep_time):
         self.stopped = False
 
     def write(self, message):
-        if self.stopped:
-            raise RuntimeError("Can't write on stopped sink")
+        assert not self.stopped
 
         length = len(message)
         self.written += message[:length]
diff --git a/tox.ini b/tox.ini
new file mode 100644
index 00000000..5358a29f
--- /dev/null
+++ b/tox.ini
@@ -0,0 +1,8 @@
+[coverage:run]
+source = .
+
+[coverage:report]
+include = loguru/*, tests/*
+exclude_lines =
+    \#\s*pragma: no cover
+    ^\s*raise NotImplementedError\b